com.devsisters.shardcake.StorageRedis.scala Maven / Gradle / Ivy
package com.devsisters.shardcake
import com.devsisters.shardcake.interfaces.Storage
import dev.profunktor.redis4cats.RedisCommands
import dev.profunktor.redis4cats.data.RedisChannel
import dev.profunktor.redis4cats.pubsub.PubSubCommands
import zio.stream.ZStream
import zio.stream.interop.fs2z._
import zio.{ Task, ZIO, ZLayer }
import scala.collection.compat._
object StorageRedis {
type fs2Stream[A] = fs2.Stream[Task, A]
type Redis = RedisCommands[Task, String, String] with PubSubCommands[fs2Stream, String, String]
/**
* A layer that returns a Storage implementation using Redis
*/
val live: ZLayer[Redis with RedisConfig, Nothing, Storage] =
ZLayer {
for {
config <- ZIO.service[RedisConfig]
stringClient <- ZIO.service[RedisCommands[Task, String, String]]
pubSubClient <- ZIO.service[PubSubCommands[fs2Stream, String, String]]
} yield new Storage {
def getAssignments: Task[Map[ShardId, Option[PodAddress]]] =
stringClient
.hGetAll(config.assignmentsKey)
.map(_.flatMap { case (k, v) =>
val pod = if (v.isEmpty) None else PodAddress(v)
k.toIntOption.map(_ -> pod)
})
def saveAssignments(assignments: Map[ShardId, Option[PodAddress]]): Task[Unit] =
stringClient.hSet(
config.assignmentsKey,
assignments.map { case (k, v) => k.toString -> v.fold("")(_.toString) }
) *>
pubSubClient
.publish(RedisChannel(config.assignmentsKey))(fs2.Stream.eval[Task, String](ZIO.succeed("ping")))
.toZStream(1)
.runDrain
def assignmentsStream: ZStream[Any, Throwable, Map[ShardId, Option[PodAddress]]] =
pubSubClient.subscribe(RedisChannel(config.assignmentsKey)).toZStream(1).mapZIO(_ => getAssignments)
def getPods: Task[Map[PodAddress, Pod]] =
stringClient
.hGetAll(config.podsKey)
.map(_.toList.flatMap { case (k, v) => PodAddress(k).map(address => address -> Pod(address, v)) }.toMap)
def savePods(pods: Map[PodAddress, Pod]): Task[Unit] =
stringClient.del(config.podsKey) *>
stringClient
.hSet(config.podsKey, pods.map { case (k, v) => k.toString -> v.version })
.when(pods.nonEmpty)
.unit
}
}
}